In VPATs that you've seen do they discuss third-party libraries that a site may use that has issues? In general with things we've done most of our stuff is actually fairly good (color contrasts, keyboard accessibility, etc), with the part I'm sketchy on the most is screen reader support since we've only done testing primarily in NVDA and some ChromeVox and VoiceOver. Not having a JAWS license has made me a little worried. That said, some of our third-party libraries that we use have issues and I've been trying to get them either replaced, or updated.